<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
        * {
            margin: 0;
        }
        .flex {
            display: flex;
        }
        .left {
            width: 100px;
            height: 100px;
            background-color: #fac;
        }
        .right {
            width: 200px;
            height: 100px;
            background-color: #fca;
            order: 2;
        }
        .center {
            flex-grow: 1;
            background-color: #cfa;
            height: 200px;
            order: 1;
        }
    </style>
  </head>
  <body>
    <div class="flex">
      <div class="center"></div>
      <div class="left"></div>
      <div class="right"></div>
    </div>
  </body>
</html>

